Launch Services is a core service of the Mac OS that enables an actively running application to open other apps, documents, or URLs (Uniform Resource Locators). Launch Services is also used to prioritize which app is used to open a document or URL.

Launch Services replaced a number of earlier system managers the Mac used to use, such as the Desktop Manager, Internet Config, and File Manager, replacing them with the single Launch Services system, and the database Launch Services maintains to keep track of all things related to how documents and apps relate to each other.

Launch Services allows an app or document to:

Open (launch or activate) another app.

Open a document or URL.

Identify the preferred app to use to open a document or URL.

Register the type of documents or URLs an app is capable of working with.

Keep track of information needed for displaying a file or URL, including its icon, name, and kind (examples: JPEG, PDF, Folder, Volume).

In past versions of the Mac OS, this type of information was maintained by the Finder, as well as by some specific system managers. By consolidating this information to the Launch Services, it allows for greater reliability, easier (actually, automatic) registration of file and document associations, and less need to repair file association information. If you remember having to rebuild the Desktop frequently on older Macs, then you know the file associations tended to get out of whack often.

Launch Services maintains a database aptly known as the Launch Services Database, which is used to record all the needed information about apps, documents, and URLs to determine which items an app is capable of working with.

Application Registration
Launch Services automatically registers an app with the database the first time the app becomes known to the system. This can occur when:

The Finder reports an app has been added to the Applications folder.

An app installer is run.

When a document is opened that has no preferred app, the user is asked to select an app to use, and that app is registered with Launch Services.

When the built-in Launch Services tool is run whenever you boot your Mac or login as a user. This tool scans the Applications folder looking for any new apps that have been placed there.

Opening Documents
When you open a document or URL, Launch Services is used to determine which app to use to open the item. Launch Services uses the following specific order to check for which app to use:

One of the first steps in installing macOS Mojave is acquiring the Mojave installer from the App Store. While this is generally an easy process, it can have a few twists and turns that can leave you frustrated.

In this guide, we take a look at:

How to download the macOS Mojave installer

Problems you may encounter, including how to convert from beta testing to using the release version

Other issues you may experience

Before you start downloading, you should check to see if your Mac is able to run Mojave. You will find all the information you need in the Rocket Yard Guide: How to Get Ready for macOS Mojave.

How to Download Mojave

The Mac App Store is the primary host for macOS Mojave, and it’s likely that the new OS will be prominently displayed under the Featured tab. But finding the macOS Mojave tile at the top of the Mac App Store window isn’t guaranteed, especially immediately after Mojave is launched or down the road, when the release of macOS Mojave is yesterday’s news.

You’re much more likely to find macOS Mojave listed in the Quick Links area of the Featured section, either with its own link to the download page, or by using the Apps Made by Apple link. And of course, you can always use the App Store’s Search field if Mojave isn’t showing up in the expected places.

To find macOS Mojave, launch the Mac App Store by selecting the App Store icon in the Dock, or by selecting it from the /Applications folder.

The App Store window will open. Click or tap the Featured button in the toolbar if it isn’t already highlighted.

There’s a good chance that macOS Mojave will be the featured item, displaying prominently at the top of the window. You may also see a button labeled Download directly on the tile; if so, clicking or tapping the button will start the download process.

If you don’t see the download link on the tile featuring macOS Mojave, click or tap the tile to bring up the description page. You’ll find the Download button near the top left. Click or tap the button to start the download process.

When the downloading process is complete, a file called Install macOS Mojave will be present in your /Applications folder. The Mojave installer will also automatically start up once the download is completed. At this point, we suggest you quit the installer in order to perform some housekeeping chores before you start the installation of macOS Mojave.

If you’ve been testing the Mojave beta on your Mac, you’ve probably already discovered the Mac App Store has undergone a substantial update. If you haven’t peeked at the Mac App Store lately, go ahead and launch it, just to get your feet wet.

Because you’re already running macOS Mojave (in the beta form), you won’t see the new OS as a download option in the new Mac App Store. Instead, you’ll be able to update your beta copy to the Gold Master (GM) version using System Preferences. We’ll touch on how to download the GM version in a bit, but first a bit more about the new App Store.

The new App Store uses a two-pane interface, with a sidebar on the left and a larger pane on the right. The sidebar contains seven primary categories into which all apps in the store are sorted. When a new macOS version becomes available, you’ll see it promoted in the Discover category. This also happens to be the default category that’s displayed when you launch the App Store.

When you see an app such as a new version of macOS displayed, you can click or tap on its tile to bring up the description page. The Download button has been replaced with one that either shows the price for the app or, if it’s a free app such as the macOS, displays the word Get. Clicking or tapping the price button will change the button text to Buy App; clicking or tapping the Get button will change the button text to Install.

You’ll need to click or tap the Buy App or Install button to start the download process.

Upgrading From the Beta
If you’re a beta tester, you may have a slightly more difficult time upgrading than the rest of us; it all depends on whether you installed the new APFS (Apple File System) during the beta testing. Apple backed away from its original goal of having APFS ready to go for all Mac configurations. Instead, it’s releasing macOS High Sierra with APFS only for Macs using SSDs (Solid State Drives). If you converted a Fusion drive during the beta, it needs to be reverted to HFS+ before you can install macOS High Sierra.

Unfortunately, Apple isn’t providing any tools to revert the file system. Instead, you’re required to back up your current data with Time Machine, erase and reformat the affected drive(s), install macOS High Sierra, and then migrate your backed up data to the fresh install.

Apple includes instructions for the process, specifically using Time Machine as the backup app. It seems you should also be able to perform this task by creating a clone using Carbon Copy Cloner or one of the other popular cloning tools. Nevertheless, even if you decide to create a clone, we highly recommend you also create a Time Machine backup, especially if the clone is the only copy of your data you will have.

You’ll need a drive partitioned as HFS+ for the Time Machine backup. This can be an existing Time Machine drive as long as it’s formatted as HFS+. You’ll also need to create a bootable macOS High Sierra installer; a 16 GB or larger USB flash drive or an external drive can serve this purpose.

Warning: The process of creating the bootable installer will erase the contents of the selected drive volume.

Apple has posted instructions in its support area for Preparing Your Fusion Drive Mac for the macOS High Sierra Install. It covers two methods for converting a Fusion Drive back to HFS+ and installing macOS High Sierra. The instructions are a bit sparse, but should be sufficient for getting the job done. If you have any questions regarding the process, be sure to post them in the Comments section below.

Boot Camp and Boot Camp Assistant allow you to install Windows on your Mac. It’s a nice capability that lets you select – at boot time – which operating system you wish to use: Mac OS or Windows.

One of the downsides to Boot Camp and the Windows installer is that it restricts you to installing Windows on your Mac’s internal drive. While Boot Camp Assistant can partition your startup drive for you to make room for Windows, there are bound to be many of you who just don’t have room to spare on your startup drive to install Windows.

Installing Windows on an external drive would be a great solution to the problem of available space, but as we said, Boot Camp and Windows impose a restriction on installing to an external drive – or do they?

There are actually a few ways you can successfully install Windows on an external drive. They range from creating clones of an existing PC installation, or using Microsoft IT tools for installing Windows. But the method we’re going to outline here is a bit different. It allows you to install Windows on an external drive without first having Windows installed on a PC or in a virtual environment.

This is an advanced process with quite a few pitfalls that can trip you up. Be sure to read through the process before undertaking it. Also, make sure you have a current backup before beginning.

With each new release of the Mac OS, there always seems to be new features that change how you work, the removal of a feature or two that forces you to rethink how you work, or just plain bugs that make working on your Mac not quite the pleasant experience it used to be.

The result is that when you visit a web page that relies on these older technologies, you may be greeted with just a black page, or a black page with a dropdown sheet asking if you wish to use Flash or one of the other disabled plug-ins on the specific website.

Although the wording can change slightly depending on the plug-in involved, you have the choice of activating the plug-in just this time for this website, always for this website, or to leave the plug-in turned off.

Your choice isn’t permanent; you can change the selection at anytime within Safari Preferences.

Select Preferences from the Safari menu.

Choose the Security tab.

Click the Plug-in Settings button.

Select a plug-in from the displayed list, and a list of websites you’ve visited that use the plug-in will be displayed. You can use the dropdown menu to change whether a plug-in may be used on the site.

You can select Off, On, or Ask. You can also specify the default for the plug-in’s use when visiting new websites.

You may be tempted to just turn the plug-in on for all websites, which would make browsing the web easier. But that choice comes with issues, including security concerns involving plug-ins, such as Flash, that seem to have a never-ending supply of vulnerabilities. Instead, we recommend using the Ask setting, which will cause Safari to ask what you wish to do each time you visit a website. This way, you’ll always know which sites are using antiquated technologies.

Upgrading from a previous version of OS X is the most common method of installing OS X Mavericks. An upgrade install also offers at least two benefits over a standard install; it’s a simple process, and it retains almost all of your settings, files, and apps from the version of OS X that you’re currently using.

Image courtesy of Apple

You may be wondering what the phrase “almost all” in the above sentence means. Mavericks will check to make sure that all of your apps are compatible with the OS; apps that won’t work with Mavericks will be moved to an Incompatible Software folder.

In addition, it’s possible that some preference settings, particularly for the Finder, will need to be reconfigured. That’s because the Finder, along with other parts of the OS, includes some changes that will require you to modify preference settings to meet your needs.

Aside from these minor inconveniences, performing an upgrade install of OS X Mavericks is pretty straightforward.

In all the operating systems running on all of the computers in the world, there is likely nothing easier than performing an upgrade install of macOS Sierra on a Mac. While not quite push-a-button-and-go, it comes close.

So, you may be wondering why there’s a need for a step-by-step guide to performing an upgrade install of macOS Sierra. The answer is a simple one. Readers like to know in advance what to expect from the macOS Sierra install process, and, since the name for the Mac operating system has changed, whether that also means there are any new requirements for the install.

The advantage of the ability to create a bootable installer of macOS Sierra can’t be overstated. It allows you to perform a clean install, which completely replaces the contents of your Mac’s startup drive with a brand-new, fresh install of Sierra.

Image courtesy of Apple

The bootable installer can also be used to install macOS Sierra on multiple Macs, without having to resort to downloading the installer app from the Mac App Store each time. This can be a pretty nice feature if you have a problematic or slow connection to the Internet.

OS X and macOS have had the capability to create install media for quite a while, but this isn’t widely known, for two reasons. First, the command to create the bootable installer is well hidden within the installer that’s downloaded from the Mac App Store; and secondly, the installer you download has a really annoying habit of automatically starting up once the download is complete. If you then click the install button, you’ll find that the installer you downloaded is automatically deleted as part of the normal installation process, preventing you from using it to create a bootable macOS Sierra installer of your own.

macOS Sierra will see its first public beta release in July of 2016, followed by a full release in the fall of 2016. Along with giving the operating system a new name, Apple is adding a lot of new features to macOS Sierra. This isn’t just a simple update, or a bunch of security and bug fixes.

Instead, macOS Sierra will add brand new features to the operating system, including the incorporation of Siri, expansion of Bluetooth and Wi-Fi based connectivity features, and a whole new file system that will replace the venerable but quite outdated HFS+ system that Macs have been using for the last 30 years.

When an operating system encompasses such a wide range of new features and capabilities there’s bound to be a few gotcha’s; in this case, the list of Macs that will support macOS Sierra will be trimmed back by quite a bit. This is the first time in five years that Apple has removed Mac models from the list of supported devices for a Mac OS.

The last time Apple dropped Mac models from the supported list was when OS X Lion was introduced. It required Macs to have a 64-bit processor, which left the original Intel Macs off the list.

The WWDC 2016 keynote kept to the script, providing previews of the four major Apple software platforms: watchOS, tvOS, macOS, and iOS. You may notice OS X is missing from the list, but only in spirit. As we mentioned in our WWDC 2016 rumor roundup, OS X underwent a name change to bring it into alignment with the naming conventions used for Apple’s other operating systems, transforming it from OS X to macOS.

Image courtesy of Apple

The name change appears to be strictly a branding change, and not an indication of any merging (current or future) of OS X and iOS into a single monolithic operating system.